Lawrence Livermore National Lab scientists are researching additive manufacturing techniques such as building multiple materials into the same product

One day a 3D printer, using a mix of materials, will be able to create body armor for U.S. soldiers that is more lightweight and stronger than anything could be made with traditional manufacturing and materials today.

That's the word from researchers at the Lawrence Livermore National Laboratory, who are working to revolutionize 3D printing, as well as the way that companies build products ranging from jet engines and satellites to football helmets.

Scientists at the laboratory, a federally funded center in Livermore, Calif., that focuses on national security research, are working on architecting new materials to be used in a process called additive manufacturing, more commonly known as 3D printing, and developing a technique for building multiple materials into the same product.

They're also studying the physics and chemistry at the base of the process in order to better understand how manufactured parts will stand up to conditions such as heat and stress, so they can predict a product's behaviors and performance.

Their research could provide critical information to any company building parts for machines ranging from automobile engines to planes, satellites and spacecraft.

"It's going to revolutionize manufacturing," said Eric Duoss, a materials scientist and engineer at the lab. "It's going to revolutionize it in terms of manufacturing itself. It's about the ability to tailor properties and achieve property combinations that would have been previously impossible to create."

Additive manufacturing, or 3D printing, is the process of creating a three-dimensional object by laying down successive layers of material. The technology has received wide media attention over the past year with 3D printers that build handguns, phone parts and toothbrushes among other things.

Duoss emphasized that the work they're doing won't change the landscape of 3D printing, but it will change the way many companies think about creating their products.

"Hopefully it will be a new way of manufacturing with a lot more possibilities and less cost, time and real estate needed to manufacture things," he said.

Pete Basiliere, a research director at Gartner Inc., said many universities and labs are working on 3D printing, but Lawrence Livermore has the resources to push the technology ahead.

"The key is that this opens the door for designers to create items that were not possible before," Basiliere said. "Engineers and designers would have another set of tools that enable them to be more creative in coming up with a product."

NASA also has talked about the benefits of using a 3D printer in space that would enable astronauts to create spare parts and even food on the International Space Station or on future deep space missions to Mars or asteroids.

Less of an art and more of a science

Lawrence Livermore researchers want to enable manufacturers to not only build more using additive manufacturing, they want to be able to build things that are impossible to build with traditional methods today.

Part of what they need to advance the technology is to understand, at a cellular level, what happens during the manufacturing process.

"We're trying to make it less of an art and more of a science," said Diane Chinn, a division leader with Livermore's materials engineering division. "We need to predict how the part is going to perform."

To get down to the science, researchers want to understand every grain inside a manufactured component. To do that, they are using data mining and a computer cluster with 160 processors, and they're developing algorithms and computer code to study the process at the microscopic level.

"What are the stresses that build up in the part as the layers are added?" asked Bob Ferencz, a group leader in the lab's Methods department. "As you melt new materials, the materials below are still being residually heated. How are those materials being affected by being heated again and again?"

Change the structure, change its properties

Scientists at the lab also are working to alter the materials used in additive manufacturing.

A material's properties -- its strength, density and the way it reacts to heat and stress -- are largely based on its underlying microstructure. By redesigning that microstructure, scientists can create materials with a combination of properties that don't exist in nature.

Duoss said Lawrence Livermore researchers are looking at the fundamental science and engineering of the materials, such as powdered metals and polymers, that are used to manufacture products. The idea is that by changing the pattern or shape of a material's cell structure, it will change its properties.

"We can take the complexity of the design space and create microscale architectures that give you control over normal properties," he said. "We can take the same base material ... and by changing the architecture of it, we can make it stronger, more lightweight and make it react differently to heat."

Duoss explained that altering the base architecture of a material can affect the way the material responds to heat or stress. A company building a car or a jet engine, for example, might want to build it with parts made of a metal that doesn't expand or lose strength when heated.

"With the design, you can control thermal expansion," Duoss said. "We could design it so when it heats up, it actually contracts... The way the structure is set up, it can handle heat better or basically be a-thermal. On the land it can be one temperature, and in space another, but it will still hold its shape."

Robert Parker, an analyst with research firm IDC, said creating a wider array of materials to use in additive manufacturing would be a key development.

"Certainly, one of the limiting factors to wider deployment of additive is the current range of materials," Parker said.

Lawrence Livermore scientists also want to go beyond using additive manufacturing to make something out of a polymer, or a mix of plastics. They want to develop a technique where one additive manufacturing machine could use materials such as a polymer and metal to create one object.

By using multiple materials, a product could be made with a sensor built inside of it.

For instance, by using different metals or a combination of metals and polymers, a 3D printer could make body armor for soldiers or police officers that is stronger, yet lighter, than anything that could be produced by layering materials on top of each other in traditional manufacturing today.

Using different metals and polymers, also would make it possible for a company to print the custom-fit foam and padding for the inside of a football helmet that would be laced with sensors. With the sensors built inside the foam, the number, and severity, of hits a player takes on the head can be tracked, helping to keep athletes from suffering brain injuries.

That kind of advance in manufacturing, said Basiliere, would be helpful to a lot of companies.

"Well, you can get a printer that can print with three different plastics," he added. "They're the same material but different colors... If someone was to come out with the ability to print with different materials, one could be a base to carry another material that could carry an electric charge. Then you could reduce a two-step operation to one step. That could increase quality and reduce price."